The section of Colinial Marines that's currently doing the rounds is short but very busy: you go on board the Sulaco, you wander about in the dark for a bit, you're teased by the enemy, and then they attack en masse. There's some lovely scripting as Xenos dart around in your peripheral vision and pop up where you don't expect them, but a lot of these moments can come directly out of the AI, too, by the sounds of it. “Xeno AI is quite different to human AI,” Brian Burleson, Colonial Marines' senior producer explains. “Aliens can climb on any surface, for starters. Also, they're meant to be really sneaky and they're meant to run about and hunt you. The Xenos are strategic. They don't necessarily want to kill you, but they do want to drag you away and make little aliens out of you, so they're really going to use the environment and its dark corners. The lighting's really dynamic, and the aliens use the lights to do their navigation. If you turn off the lights, their navigation changes completely.”

To ward against such a nimble threat, players have handy gadgets like the classic Aliens motion tracker. When you're looking at that, though, you aren't able to shoot. The key to success, in other words, lies with making the most of your squad. “When you're by yourself, you feel pretty vulnerable, because aliens can kill you pretty quickly and pretty easily,” says Brian. “When you're with your squad, they make you feel powerful. So you really want to keep them alive.

“It's not a fair set-up, basically. You've got to be smart, you've got to use your tools well, and that adds a tension that isn't usually in games. It's brutal. When you watch multiplayer, for example, with first-person shooters, you normally see people just running around and shooting stuff. Do that here and you'll die in, like, under a second. So what happens here is the marines naturally start clumping together. They start pulling out motion trackers, organising who shoots and who tracks, and working together. The Xenos, meanwhile, are basically melee characters, right, so they have to be really strategic and wait and watch in the darkness, looking for anyone who's become separated. Xenos don't have much health, so if they just run straight into a group of marines, they'll die pretty quickly too.”

What really stands out from the demo, though, isn't the AI and the possibilities it offers for tactical combat so much as the care that's been taken in recreating the world of Aliens. The Sulaco's suitably futuristic, for example, but it's the future of the 1980s you're seeing: big, rounded monitors, heavy keyboards, and wire-frame images on every computer screen. I'm mildly surprised Cameo doesn't invite you on board holding a pencil mic and clad in some kind of glitzy plastic jockstrap. Word up.

“The thing we were really interested in doing when we were saying, “Okay, this is a sequel, this is legit,” is that we had to get all the pieces together from the people who had made the original film,” says Brian, lithely dodging all of my Cameo speculation. “Fox was great with that: they gave us source references, contacts. We got all these CDs of set photos, and stuff that nobody else has ever seen. That's why it's all retro tech in the game: it's all CRTs and old keyboards. You think in the future they'd have other things, right? There's definitely an aesthetic from the film there that you want to keep going, and it's actually kind of charming. You're typing on a keyboard, there's a tiny CRT screen on this dresser-sized device. That seemed really important.”

Making an official sequel to Aliens brings with it its own problems of course - not least the fact that games have been coming up with unofficial sequels for years, and giving them names like 'Halo'. “It's just such a huge part of popular culture,” admits Brian. “Halo, you've got the space marines, Call of Duty, you've got that sergeant yelling at you. It's pretty ridiculous. The fact that we have the license helps a lot: everybody knows what Aliens is and that has a lot of resonance. It's interesting, though. We did some focus testing, trying to work out what people perceive the game as being, and youngest gamers, they weren't alive when the movie came out, their points of reference are the recent games that have referenced the movie. They'll play the game and say, “Oh, that sounds like something that was said in COD,” and we'd be like, “ Actually , it was said in Aliens.””

He pauses, and then laughs. “It's funny, I guess. In sort of a meta way.”